‘nature-based’ blue-green-grey

infrastructure solutions

Dr Mark FletcherGlobal Water Leader

MILLENIUM PARK CHICAGO

outline

context

blue + green + grey methodology

global examples

case study 1 New York City

case study 2 Rainscape Wales

conclusions

CENTRAL PARK NEW YORK

MANCHESTER, FROM KERSAL MOOR EDWARD

GOODALL (1795-1870), AFTER A PAINTING BY W. WYLDE.

context | start with grey

Pumps, pipes, concrete still have

a role to play

* UNITED NATIONS – WORLD URBANISATION PROSPECTS (2010)

SHIBUYA, TOKYO

“by 2050, 70% of people will live in

cities”

© S

HU

TT

ER

SC

OC

K

BANGKOK 2011

“climate change is costing the world more than $1.2 trillion

annually”

CITY CHALLENGES

WETLAND & WILDFOWL CENTRE, LONDON

blue + green + grey

methodology

‘nature-based’

retrofit existing cities

masterplan new cities

Work with nature-based thinking across the water cycle

Use green + blue space – create, expand, adapt

Capture, store, treat and release

Cools, attenuates, provides amenity and recreation and improves landscape

Design places using vegetation

Natural/semi-natural: bush, tree, copse, wood, forest, meadow, wetland

Man-made: green roof, planter, flowerbed, park, field, footpath, hedgerow

green thinking

Eg encourage

Urban Forest

Work with nature-based thinking across the water cycle

Use green + blue space – create, expand, adapt

Capture, store, treat and release…. and provide continuity across the water cycle

Design places to use water practically and creatively

Provides amenity and recreation benefits

Natural/semi-natural: puddles, pools, ponds, lakes, streams and rivers

Man-made: Taps, toilets, reservoirs, canals, swales, fountains, ditches and drains

blue thinkingEg de-culvert Urban

Watercourses

environmental benefits economic benefits social benefits

Improved visual amenity Increased resilience Encouraging physical activity

Enhanced microclimate Increased land values Improving childhood development

Improved air quality Faster property sales Improved mental health

Reduced flood risk Encouraging inward investment Faster hospital recovery rates

Better water/ soil quality Reducing building energy costs Lowering stress

Water storage and reuse Faster planning permission Improved workplace productivity

Improved biodiversity Improving areas for tourism Increasing social cohesion

Reducing ambient noise Lowering healthcare costs Reducing crime

some of the benefits of urban blue + green infrastructure

EXETER UNIVERSITY HEALTH RESEARCH – 5,000

HOUSEHOLDS OVER 17 YEARS

*‘PEOPLE IN GREENER AREAS REPORTED LOWER LEVELS OF STRESS AND HIGHER DEGREES OF LIFE SATISFACTION’

*

“contact with nature lowers stress levels and improves life satisfaction”

PUGH T, MACKENZIE A, WYATT J, HEWITT C, ‘EFFECTS OF GREEN

INFRASTRUCTURE FOR IMPROVEMENT OF AIR QUALITY IN URBAN

STREET CANYONS – ENVIRONMENT, SCIENCE + TECHNOLOGY (2012)

‘GREEN+ BLUE STREETS CAN CUT POLLUTION BY

30%’

)

*

“urban blue + green streets cut pollution & clean the environment”

FORESTRY COMMISSION UK (2010) ‘THE CASE FOR TREES IN DEVELOPMENT AND THE URBAN ENVIRONMENT’

**RESIDENTS IN GREEN ENVIRONMENTS WERE 3.3 TIMES MORE LIKELY TO TAKE FREQUENT PHYSICAL EXERCISE’

“a green + blue environment stimulates better physical health”

HERRERA ENVIRONMENTAL CONSULTANTS (2008) ‘THE EFFECTS OF

TREES ON STORM WATER RUNOFF

‘URBAN GREEN CAN SLOW DOWN & REDUCE STORM WATER RUNOFF BY UP TO 8%’

*

“urban wetland and permeable surfaces provide flood resilience”

THOMAS AM, PUGH A, MACKENZIE R, WHYATT JD, (2012)

‘EFFECTIVENESS OF GREEN INFRASTRUCTURE’

(LANCASTER ENVIRONMENT CENTRE)

‘SURFACE TEMPERATURE REDUCED BY 13°C UNDER A MATURE TREE CANOPY’

*

“urban blue + green creates better microclimates, cooling and shade”

blue + green thinking helping to create liveable cities

Project

Identification

Design

Development

Options

Appraisal

Financial and

Commercial

Analysis

Detailed

Design and

Construction

Operations and

Maintenance

blue + green + grey thinking“nature-based’

methodology

New York City | addressing water

quality in New York City

blue + green + grey New York

blue + green neighbourhood in Hunter’s Point South, New York

3rows of Bioswales

on 51st Ave

3,400linear feet new roads,

water and sewer

92enhanced tree pits

33% of sidewalks are

porous pavement

blue + green + grey retrofit

in New York

© Arup

blue + green + grey

retrofit in New York

blue + green + grey retrofit New York

RainScape Wales | protecting shellfish waters from sewage pollution

in Wales

“DCWW firm to be sentenced for estuary

sewage pollution”

Evening Post

grey storage solution

Required Storage: 433,000m³

Cost: £600million

blue + green solutions

blue + green retrofit solutions in schools

Before

blue + green + grey retrofit swale in schools

Before After

blue + green + grey

retrofit downpipe planters

blue + green + grey stormwater attenuation basins

blue + green + grey stormwater attenuation planter

blue + green + grey solution performance

Conclusions

TNC Goal to develop an informed dialogue with funders on co-optimised blue-green-grey solutions

• Catchment scale modelling essential

• Evaluate blue, green and grey options including ‘nature-based’ thinking

• Learn from pilot studies – monitor and evaluate

• Use economic, social and environmental cost benefit assessment

• Incorporate capital, operational and maintenance costs and issues

• Develop a bench-marking tool

‘nature-based’ blue-green-grey

infrastructure solutions

Dr Mark FletcherGlobal Water Leader

MILLENIUM PARK CHICAGO